Culvert.



A. REUTERDAHL.

GULVERT.

APPLIOATION FILED MAY 3, 1911.

Patented June 4, 1912.

WITNESSES INVENTOR ARVID REUTERDAHL, or BOISE, IDAHO.

GULVERT.

Specification of Letters. Patent.

Patented June 4, 1912.

Application filedMay 3, 1911. Serial No. 624,831.

To all whom it may concern: 7

Be it known that I, ARVID REUTERDAHL, a citizen of the United States, residing at Boise, in the county of Ada and State of Idaho have invented a new and useful Culvert, of which the following is a specification.

My invention relates to improvements in culverts and more particularly to nestable culverts made in sections and constructed of such material as either .iron or steel or other suitable metal.

The objects of my improvement are first, to provide a culvert free from rivets or bolts which are liable to disintegration due to electrolysis or similar causes; second,

to provide for the expansion caused by the freezing of water within the culvert; and, third, to provide a simple means of positively interlocking the sections of the culvert without resorting to auxiliary parts or members riveted or bolted to the main sections of the culvert. I attain these objects by the device illustrated in the accompanying drawing, in which the figure is a par-' tial side view of the top and bottom sections of the culvert.

The top section A in the figure is provided with teeth or denticles a which pass into the cavities 6 provided in the bottom section B. The cavity or aperture 6 is produced in the bottom section B by forcing the retaining strip at outward from the ex terior surface of section B, said retaining strip cl being integral with and formed out of the main body of section B by first making two incisions or cuts, preferably parallel as shown, in the metallic sheet B; then said retaining strip cl is forced outward from the surface of the sheet B by means of suitable appliances and machines thus leaving a cavity Z2 which can contain and engage the tooth or denticle a which is integral with section A. The tooth or denticle a is inturn provided with an auxiliary looking tooth c which is produced by cutting through the metal of the main tooth a, leaving the lower part of the auxiliary looking tooth c integral with said main tooth. The auxiliary locking tooth o is thus released from the body of the main tooth a on all sides except the lower where it is permanently held and retained to. said main tooth a. The auxiliary locking tooth c is then forced slightly outward along its upper edge from said main tooth on. The

elasticity of the metal from which section A is made will cause the auxiliary locking tooth c to retain its outward deflection. Hence when the main tooth a is forced into the cavity Z2 sufficiently far to allow the auxiliary locking tooth c to clear the retainingstrip cl, said auxiliary locking tooth 0 will spring outward due to the elasticity of the material thus locking section A to section B and preventing the two sections from being permanently pulled apart or detached. However, it is evident that relative motion betweensection A and section B is, nevertheless, possible within a limited latitude without permanently disengaging section A from section B. This relative, though limited, motion is a most essential featureof this improvement for upon this very characteristic is founded the possibility of providing for expansion due to the freezing of water within the culvert during cold weather.

It is not essential that the auxiliary looking tooth 0 shall project above the lower edge of the retaining strip d. All that is necessary for the successful operation of this improvement is that the upper edge of the auxiliary locking toot-h 0 can abut with the lower edge of the retaining strip 0?. The main tooth or denticle a is in either case made of sufficient length to allow for the relative motion of section A and sect-ion B due to expansion. I

In carrying out the principles of this invention semicircular or other suitably shaped sections are made; one set is provided with a number of main teeth a and the other set is provided with cavities or apertures 73 and retaining strips d. Top sections as well as bottom sections are lapped slightly. The laps are staggered by placing the top sections in such a relative position to the bottom sections that the mid-point of the top section coincides with the point of lap in the bottom sections. At the two extremities of the culvert half-top sections therefore are necessary to complete it.

It is evident that the relativeposition of section A and section B may be reversed, section A being made the bottom and section B the top. Furthermore it is clear that the retaining strip (Z may be forced inward in which case section A must pass on the inside of section B. Moreover, it is seen from the nature of the device that it is applicable to either smooth or corrugated provided with teeth or dent-icles a and the- 'these specifications.

denticles projecting therefrom, with a section provided with displaced retaining strips integral with said section and cavities or apertures produced in said section by these displacements of the retaining strips, said apertures containing and engaging said. teeth or denticles, all substantially as set forth. other edge would contain the retaining 2. The combination, in a culvert, of a strips (Z and the apertures 72. In such a suitably formed section having teeth or section where the two longitudinal edges of denticles projecting therefrom, said teeth the sheet are brought together and united being provided with auxiliary locking teeth by means of the device herein set forth, the protruding therefrom, with a section pro-- various one part or single sheet sections may vided with displaced retaining strips inbe joined and connected along the peripheries of the sections at the places where they abut by the same device described in By this means culverts of indefinite length may be built-up by using merely the present device in connecting the sections to each other along thevlength of the built-up culvert.

Having thus described my invention I claim:

1. The combination, in a culvert, of a suitably formed section having teeth or culvert construction. In the case of a corrugated culvert the retaining strip d and the main tooth a is preferably formed from the 1 metal in the indentations.

My invention is equally applicable to a one part section of a circular or other suitable form. In this case one edge would be apertures produced in said section by these displacements of the retalning strips, said apertures contalning and engaging said teeth so disposed that they can engage or abut with said retaining strips, substantially as setforth.

ARVID REUTERDAHL. l/Vitnesses:

CHARLES P. MCCARTHY, RAYMOND L. GIvENs.

K Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C.

tegral with said section and cavities or teeth or clenticles, and said auxiliary locking 5 

